Atrial Septal Defect Primum

  • (Also called 'Partial AV Septal Defect')

    A defect is present in the lower part of the "Atrial Septum" (the partition separating the Atriums). This allows red blood to pass through into the right side of the heart, leading to enlargement of the right ventricle and excessive flow in the lung circulation. This type of ASD is less common than the "central" (Secundum) defect.

    Defects of this type are more likely to lead to symptoms during childhood.  Abnormalities of one or more heart valves (especially the Mitral Valve) frequently coexist with defects of this type and and may result in early onset of symptoms with breathlessness, poor feeding and slow weight gain.


    These defects require surgery and cannot be closed with a 'Device'.  The operation involves sewing a patch over the defect and repairing the abnormal valve (Mitral Valve) which usually needs to be attended to, to try to stop it 'leaking' - a problem which is usually present in children with this type of defect.